This invention relates generally to methods and apparatus for monitoring myoelectric signals from an organ to aid in the diagnosis of various disorders. The general term for the system of the invention is an electroviscerogram (EVG) system which measures myoelectrical activity from various organs within the abdominal cavity. Specifically, this invention relates to the use of an electrogastrogram (EGG) and analysis of electrogastrograms to diagnose recorded signals associated with functional dyspepsia and other functional or neuromuscular disorders of the gastrointestinal and urinary tract.
Nausea is a vague and sometimes difficult to describe xe2x80x9csick to the stomachxe2x80x9d sensation that may evolve into an urge to vomit if the nausea becomes severe. Nausea often is a debilitating and depressing symptom. Nausea and vomiting may present as acute and self-limited symptoms that accompany a variety of diseases and disorders. For the family physician, internist, or gastroenterologist who is evaluating the patient with nausea and vomiting, there are many possible causes to consider. The gastroenterologist may be asked to see such patients in consultation, particularly if the nausea and vomiting becomes chronic. These patients may be difficult to manage if standard tests such as ultrasound of the gallbladder and pancreas, upper endoscopy, and abdominal CAT scans are normal or empiric treatment does not relieve the symptoms.
Electrogastrograms have been employed to diagnose stomach disorders. However, spurious signals (artifact) are typically present in the raw EGG signals due to patient movement, breathing, etc. These spurious signals should be excluded from any calculations used to analyze the EGG signal. Typically, spurious signals such as electrocardiogram (EKG) signals are excluded by filtering the EGG signal. However, in certain instances, the spurious signals are respiratory signals that occur in the frequency ranges of interest.
Accordingly, there is a need to provide a method and apparatus to evaluate myoelectric signals from the stomach or other intra-abdominal organs to aid in a diagnosis of a disorder and to accurately identify and exclude spurious signals.
An object of the present invention is to fulfill the need referred to above. In accordance with the principles of the present invention, this objective is obtained by providing a system for processing signals indicative of the detected myoelectrical activity. The system includes electrodes to obtain first signals over time. The first signals are produced from an internal organ in the abdominal cavity of a living being and may include spurious signals as a result of artifact. A sensor obtains second signals simultaneously as the first signals are obtained. The second signals are indicative of a respiratory function of the living being and include spurious signals indicative of artifact such as movement of the body or limbs. A processor analyzes the first signals which occur at times when artifact is not present in both of the first and second signals.
In accordance with another aspect of the invention, a method of identifying artifacts in signals indicative of detected myoelectrical activity includes:
providing electrodes to obtain first signals over time, the first signals being produced from an internal organ in the abdominal cavity of a living being, the first signals including spurious signals as a result of artifact,
providing a sensor to obtain second signals simultaneously as the first signals are obtained, the second signals being indicative of a respiratory function of the living being and include spurious signals indicative of artifact,
recording the first and second signals simultaneously,
identifying when artifacts occur by noting irregularities in both the recorded first and second signals during a particular time frame.
In another aspect of the invention, a method of monitoring the myoelectrical activity of the stomach of a person includes:
mounting electrodes on an abdomen of the person to obtain a plurality of first analog signals from the stomach over time, the first analog signals including spurious signals as a result of artifact,
mounting a sensor to the person to obtain a plurality of second analog signals simultaneously as the first analog signals are obtained, the second analog signals being indicative of a respiratory function of the person and include spurious signals indicative of artifact,
consuming, by the person, water in a specific time frame until the stomach is substantially full to stimulate gastric electro-contractile activity while recording the first and second analog signals simultaneously,
continuing to record the first and second analog signals simultaneously for a period of time after consumption of water,
identifying, during the recording of the first and second signals, the occurrence of artifacts by noting irregularities in both the first and second analog signals during a particular time frame,
converting the first analog signals to digital signals, and
analyzing the digital signals which occur at times when artifact is not present.
In yet another aspect of the invention a kit is provided for use in recording myoelectric activity of the stomach of a person. The kit includes a plurality of disposable electrodes; a visual analog scale for scoring an intensity of selected symptoms at various times; and two, one liter bottles of spring water with each bottle being scored with ml marks for accurate measurement of the volume of water consumed from the bottle.
Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.